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1.
Rev. biol. trop ; 58(supl.3): 1-22, Oct. 2010. ilus, graf, tab
Artigo em Inglês | LILACS | ID: lil-638084

RESUMO

The coral reefs, seagrasses and mangroves from the Costa Rican Caribbean coast have been monitored since 1999 using the CARICOMP protocol. Live coral cover at Meager Shoal reef bank (7 to 10m depth) at the Parque Nacional Cahuita (National Park), increased from 13.3% in 1999, to 28.2% in 2003, but decreased during the next 5 years to around 17.5%. Algal cover increased significantly since 2003 from 36.6% to 61.3% in 2008. The density of Diadema antillarum oscillated between 2 and 7ind/m2, while Echinometra viridis decreased significantly from 20 to 0.6ind/m2. Compared to other CARICOMP sites, live coral cover, fish diversity and density, and sea urchin density were low, and algal cover was intermediate. The seagrass site, also in the Parque Nacional Cahuita, is dominated by Thalassia testudinum and showed an intermediate productivity (2.7±1.15 g/m2/d) and biomass (822.8±391.84 g/m2) compared to other CARICOMP sites. Coral reefs and seagrasses at the Parque Nacional Cahuita continue to be impacted by high sediment loads from terrestrial origin. The mangrove forest at Gandoca, within the Refugio Nacional de Vida Silvestre Gandoca-Manzanillo (National Wildlife Refuge), surrounds a lagoon and it is dominated by the red mangrove, Rhizophora mangle. Productivity and flower production peak was in July. Biomass (14kg/m2) and density (9.0±0.58 trees/100m2) in Gandoca were relatively low compared to other CARICOMP sites, while productivity in July in Costa Rica (4g/m2/d) was intermediate, similar to most CARICOMP sites. This mangrove is expanding and has low human impact thus far. Management actions should be taken to protect and preserve these important coastal ecosystems. Rev. Biol. Trop. 58 (Suppl. 3): 1-22. Epub 2010 October 01.


Los arrecifes coralinos, pastos marinos y manglares de la costa Caribe de Costa Rica han sido monitoreados desde 1999 siguiendo el protocolo de CARICOMP. La cobertura de coral vivo en el arrecife de Meager Shoal (7 a 10m de profundidad) en el Parque Nacional Cahuita, aumentó de 13.3% en 1999, a 28.2% en 2003, pero después bajó, por los siguientes 5 años, a aproximadamente 17.5%; la cobertura de algas aumentó significativamente de 36.6% en 2003 a 61.3% en 2008. La densidad de Diadema antillarum osciló entre 2 y 7 ind/m2 mientras que Echinometra viridis decreció significativamente de 20 a 0.6 ind/m2. Comparado con otros sitios CARICOMP, la cobertura de coral vivo, diversidad y densidad de peces, y densidades de erizos de mar fueron bajas y la cobertura algal intermedia. El sitio de pastos marinos, también en el Parque Nacional Cahuita, está dominado por Thalassia testudinum y tiene una productividad (2.7±1.15g/m2/d) y biomasa (822.8±391.84g/m2) intermedia comparado a otros sitios CARICOMP. Los arrecifes coralinos y pastos marinos en el Parque Nacional Cahuita continúan siendo impactados por sedimentos terrígenos. El bosque de manglar en Laguna Gandoca, dentro del Refugio Nacional de Vida Silvestre Gandoca-Manzanillo, está bordeado por una laguna y predomina el mangle rojo, Rhizophora mangle. El pico de productividad y producción de flores fue en julio. La biomasa (14 kg/m2) y densidad (9.0±0.58 árboles/100 m2) en Gandoca fueron relativamente bajas comparadas con otros sitios CARICOMP, mientras que la productividad en julio en Costa Rica (4g/m2/d) fue intermedia, similar a la mayoría de los sitios CARICOMP. Este manglar se está expandiendo y tiene muy poco impacto humano hasta ahora. Se deben tomar acciones de manejo para proteger y preservar estos importantes ecosistemas costeros.


Assuntos
Recifes de Corais , Ecossistema , Monitoramento Ambiental/métodos , Poaceae/classificação , Rhizophoraceae/classificação , Costa Rica , Meio Ambiente , Densidade Demográfica
2.
Rev. biol. trop ; 58(supl.1): 33-50, May 2010. graf, mapas, tab
Artigo em Inglês | LILACS | ID: lil-637953

RESUMO

Costa Rica has coral communities and reefs on the Caribbean coast and on the Pacific along the coast and off-shore islands. The Southern section of the Caribbean coast has fringing and patch reefs, carbonate banks, and an incipient algal ridge. The Pacific coast has coral communities, reefs and isolated coral colonies. Coral reefs have been seriously impacted in the last 30 years, mainly by sediments (Caribbean coast and some Pacific reefs) and by El Niño warming events (both coasts). Monitoring is being carried out at three sites on each coast. Both coasts suffered significant reductions in live coral cover in the 1980’s, but coral cover is now increasing in most sites. The government of Costa Rica is aware of the importance of coral reefs and marine environments in general, and in recent years decrees have been implemented (or are in the process of approval) to protect them, but limited resources endanger their proper management and conservation, including proper outreach to reef users and the general public. Rev. Biol. Trop. 58 (Suppl. 1): 33-50. Epub 2010 May 01.


Costa Rica tiene comunidades coralinas y arrecifes en la costa Caribe y del lado Pacífico a lo largo de la costa y en islas mar afuera). Arrecifes de franja y de parche, bancos carbonatados y una cresta de algas coralinas incipiente están presentes en la sección sur de la costa Caribe. Comunidades coralinas, arrecifes y colonias de coral aisladas se encuentran a lo largo de todo el Pacífico de Costa Rica. Los arrecifes coralinos han sido impactados seriamente en los últimos 30 años, principalmente por sedimentos en el Caribe y algunos arrecifes del Pacífico, y por el calentamiento durante el Fenómeno de El Niño-Oscilación Sureña en el Pacífico. Tres sitios en el Caribe y otros tres en el Pacífico están siendo monitoreados. Después de reducciones significativas en la cobertura de coral vivo en la década de 1980, tanto en el Caribe como en el Pacífico, la mayoría de los arrecifes se está recuperando. El gobierno de Costa Rica es consciente de la importancia de los arrecifes coralinos y de otros ecosistemas marinos, y en años recientes han implementado (o están en proceso de aprobación) varios decretos para la protección de los arrecifes. Pero, hay limitación de fondos y personal para su adecuado manejo y protección. Se necesita más divulgación de información sobre los arrecifes coralinos al público en general y usuarios de los mismos; de nuevo, la limitación de fondos restringe lo que se puede hacer.


Assuntos
Animais , Antozoários , Recifes de Corais , Monitoramento Ambiental/métodos , Costa Rica , Oceano Pacífico , Densidade Demográfica
3.
Rev. biol. trop ; 55(1): 55-66, Mar. 2007. mapas, graf, tab
Artigo em Espanhol | LILACS | ID: lil-501497

RESUMO

The seagrass of Perezoso (Cahuita National Park, Caribbean coast of Costa Rica) was monitored using the CARICOMP protocol. Productivity (2.7 +/- 1.15 g/m2/d; n=74) was intermediate, compared to other Caribbean sites. Total biomass was intermediate to high (750-1500 g/m2) at most CARICOMP sites (Colombia, Cuba, Mexico, Puerto Rico and Venezuela) including Costa Rica (822.8 +/- 391.84 g/m2; n=32). Turnover rates were high (5.5 +/- 1.36%; n=74) compared to what was found in March and August at other sites. Shoot densities average 725 shoots/m2, in the Caribbean region, while in Costa Rica the value was higher (1184 +/- 335.5 shoots/m2). Average leaf length and width in the entire region were 14.4 cm and 10.6 mm, respectively, similar to what we found, but leaf area index average 3.4 m2 m(-2), higher than what was found in Costa Rica (0.92 m2 m(-2)). At Cahuita, seagrass productivity was significantly lower in March 2005 compared with the previous six years, and biomass has decreased with time. Seagrass productivity and biomass are being affected by the maximum temperatures, which increased by almost 10 degrees C from 1999 to 2005, and show a high negative correlation. Turnover rate and temperature were not correlated. Recreational boating, swimming and nutrient loading from deforested lands in the coast, the upstream rivers and local pollution are potential sources of impact to the seagrass beds at Cahuita.


Assuntos
Alismatales/fisiologia , Ecossistema , Monitoramento Ambiental , Água do Mar , Alismatales/classificação , Biomassa , Costa Rica , Densidade Demográfica
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